I. Field of the Invention
This invention relates generally to surgical scissors, and in particular to a bipolar scissors instrument wherein the axis of distal blade members thereof is nonlinear in relation to a linear axis of the instrument proximal to the blade members.
II. Discussion of the Prior Art
Electrocauterization is a process whereby blood vessels (commonly called "bleeders") in tissue or alone which are cut during a surgical procedure are sealed closed by applying electrical energy at the site to, essentially, fuse by heat the vessel opening. In order to provide electrical energy at the site of bleeding, an instrument capable of conducting electricity must be placed at that site. The conductive instrument may be comprised of one electrode (monopolar) which cooperates with a remote conductive body plate electrode, or the instrument may be comprised of two closely spaced electrodes (bipolar). Current passing from one electrode to the other produces the heat sufficient to seal blood vessels or to coagulate blood and other fluids. A bipolar instrument is generally preferred by a physician since current travel is over a short distance. A monopolar instrument usually requires electric current to travel a relatively long distance to the body plate electrode, with current directability and effect being unpredictable and possibly harmful to a patient.
Surgical scissors are known in the art. Those available for use in endoscopically performed surgeries or other similar scope procedures are of a size to fit distally through the scope while having operating handles proximally of the scope. Generally, the scissors include a proximal scissors type handle, a central hollow tube through which a linkage from the handle passes, and a distal blade pair to which the linkage connects. Co-pending and commonly assigned patent application Ser. No. 08/013,869, filed Feb. 5, 1993, and entitled "BIPOLAR ELECTRICAL SURGICAL SCISSORS," teaches a bipolar scissors instrument wherein both of the blades thereof pivot in relation to each other. A ceramic layer is present on each of the respective inner surfaces of each blade member, and insulation means at strategic sites throughout the instrument maintain bipolar capability for the separate blade members. The central hollow tube described above and the distal blade pair lie in a single linear axis. Such a single axis can create a visibility problem in some circumstances since a view of the blade members may be obstructed by the immediately-proximal portion of the instrument because it is in the same linear axis as that of the blade members.
It is therefore a primary object of the present invention to provide a bipolar electrosurgical scissors instrument whose blade members are in a nonlinear axis in relation to a proximal linear axis of the instrument.
It is a further object of the present invention to provide a bipolar electrical surgical scissors instrument or in the blade members are arcuate or angled.
These and other objects of the present invention will become apparent in the description of the invention which follows.